Writing on the persecution of Constantius II, Vincent of Lérins quotes also Ambrose of Milan's De fide (II.16), in which Ambrose mentions confessorum neces, [et] exsilia sacerdotum ("deaths of the confessors and exiles of the priests") in the same context.
By priests, he most probably means both presbyters and bishops; compare with the passage: omnes clerici leuitae et sacerdotes ["all clerics, levites and priests"] in Commonitory XXIV.